How can I design a GUI like this example?

[Zero]

I'd like to design a GUI like the following picture.


The example is made by pygame. How can I design a window like Window 1 that a window has Window 1 and Hello World window. In addition, I can drag the Window 1. How can I design like the example in Viazrd?

I try to use vizinfo, but there is a problem that I can't put a button or other element to a position what I like.

Do you have any suggestion?

Thank you!!